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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Multikulturele onderwys in die VSA, Afrika en die RSA : 'n histories-vergelykende ondersoek en evaluering

Meier, Corinne 03 1900 (has links)
Text in Afrikaans / Multikulturele onderwys is die uitkoms van demokratiseringstendense wereldwyd. Die Verenigde State van Amerika, Zimbabwe en die Republiek van Suid-Afrika is as eksemplare geselekteer om die wordingsgang van multikulturele onderwys te ondersoek. Die wordingsgang toon duidelike ooreenkomste met die wordingsgang van gesegregeerde, monokulturele onderwysstelsels. Weerstand teen die eksklusiewe aard van monokulturele onderwys het uitgeloop op die ontwikkeling en implementering van multikulturele onderwys. In die Verenigde State van Amerika word die implementering van multikulturele onderwys wetlik afgedwing. Multikulturele onderwys in Zimbabwe word nie s6 intensiefverreken nie. In die onderwys van Zimbabwe val die klem oorwegend op Afrikanisering en lewensvoorbereiding en daarna op die optimale hantering van kultuurdiversiteit. Onderwys in die Republiek van Suid-Afrika is steeds gesegregeer en hoofsaaklik monokultureel. Dit blyk uit die beleidsdokumente van onderwysbelanghebbendes dat 'n toekomstige onderwysbedeling dieselfde weg as die in Zimbabwe gaan volg. Die onderrig van samelewingsvaardighede word as prioriteit gestel. / Multicultural education is the consequence of universal trends towards democratisation. The United States of America, Zimbabwe and the Republic of South Africa were selected as exemplars to investigate the emergence of multicultural education. There are distinct similarities between this process and that of the development of segregated monocultural education systems. Opposition to the exclusive nature of monocultural education resulted in the establishment and implementation of multicultural education. In the United States of America multicultural education is enforced by legislation. Multicultural education in Zimbabwe is not applied as stringently. Zimbabwe's educational model emphasises Africanisation and the preparation for life, also proficiency in dealing with cultural diversity. Education in the Republic of South Africa remains segregated and predominately monocultural. From the policy documents of those parties interested in education it seems that any future educational dispensation will follow a course similar to that of Zimbabwe. The teaching of societal skills enjoys precedence. / Educational Studies / M. Ed. (Historical Education)
172

Técnicas de proteção e restauração em redes ópticas elásticas / Protection and restoration techniques in elastic optical networks

Lourenço, André Luiz Ferraz 26 November 2015 (has links)
As redes ópticas estão passando por mudanças significativas, impulsionadas pelo crescimento exponencial do tráfego, principalmente advindo de serviços multimídia e armazenamento em nuvem. Esta demanda exigirá aumento da capacidade da taxa de transmissão para padrões como 400 Gb/s e 1 Tb/s. Nesse contexto, foi proposta uma arquitetura de rede com grade de frequências granular flexível chamada elastic optical network (EON). A EON divide o espectro de frequências em fatias (slots) de tamanho fixo e aloca grupos de slots contíguos estritamente de acordo com os requisitos de banda das demandas de conexão, implicando eficiência de uso do espectro. Com o aumento significativo da taxa de transmissão, acentuou-se a preocupação em manter a sobrevivência da rede, já que pouco tempo de queda no serviço pode acarretar uma imensa perda de dados. Neste trabalho, investigamos esquemas de proteção baseados em caminhos compartilhados (shared-path protection, SPP) e esquemas de restauração de tráfego. Avaliamos esquemas divulgados na literatura como o dynamic load balancing shared-path protection (DLBSPP) e esquemas de restauração como o traffic aware restoration (TAR) e bandwidth squeezed restoration (BSR). Avaliamos também uma heurística de alocação de slots chamada inverted dual stack (IDS). O DLBSPP utiliza balanceamento dinâmico de carga para computar os caminhos primários e de proteção compartilhados. O TAR executa a restauração dinâmica ordenando as conexões por granularidade de banda. O BSR utiliza a capacidade de contração de banda do EON para restaurar conexões por meio da política de melhor esforço ou de banda garantida, dependendo do acordo de níveis de serviço do cliente. O esquema IDS concentra o maior número possível de slots compartilhados em uma região do espectro. As medidas de desempenho dos algoritmos são avaliadas segundo as métricas: probabilidade de bloqueio, taxa de utilização do espectro, número médio de hops e taxa de restauração falha. As simulações computacionais mostram o bom desempenho da utilização do esquema IDS com DLBSPP. / Optical networks are undergoing significant changes driven by the exponentially growing traffic, especially coming from multimedia and cloud storage services. This demand will require increasing of the transmission rate capacity as high as 400 Gb/s and 1 Tb/s. Within this context, it was proposed the elastic optical network (EON), which is a network architecture with flexible granular frequency grid. EON divides the frequency spectrum into slices (slots) of fixed size and allocates groups of contiguous slots strictly according to the bandwidth requirement of the connection demands, providing high spectrum use efficiency. The significant increase in transmission rate put emphasis on the need to maintain the survival of the network, since the occurrence of faults in the network nodes or links can cause huge loss of data. In this work, we investigate protection schemes based on shared-path protection (SPP) and traffic restoration schemes. We evaluate schemes related in the literature, such as the dynamic load balancing shared-path protection (DLBSPP), and restoration schemes such as the traffic aware restoration (TAR) and the bandwidth squeezed restoration (BSR). The DLBP scheme uses dynamic load balancing to compute primary and shared protection paths. The TAR performs dynamic restoration ordering the connections based on band granularity. The BSR uses EON\'s band squeezing feature to restore connections by means of the best effort or guaranteed bandwidth strategy, depending on the customer\'s service level agreement. IDS scheme concentrates the maximum possible number of shared slots in a given region of the spectrum. Performance of the algorithms are evaluated according to metrics: blocking probability, spectrum utilization rate, average number of hops and failure restoration rate. Computer simulations show that the use of the IDS scheme improves the performance of the investigated algorithms.
173

Multikulturele onderwys in die VSA, Afrika en die RSA : 'n histories-vergelykende ondersoek en evaluering

Meier, Corinne 03 1900 (has links)
Text in Afrikaans / Multikulturele onderwys is die uitkoms van demokratiseringstendense wereldwyd. Die Verenigde State van Amerika, Zimbabwe en die Republiek van Suid-Afrika is as eksemplare geselekteer om die wordingsgang van multikulturele onderwys te ondersoek. Die wordingsgang toon duidelike ooreenkomste met die wordingsgang van gesegregeerde, monokulturele onderwysstelsels. Weerstand teen die eksklusiewe aard van monokulturele onderwys het uitgeloop op die ontwikkeling en implementering van multikulturele onderwys. In die Verenigde State van Amerika word die implementering van multikulturele onderwys wetlik afgedwing. Multikulturele onderwys in Zimbabwe word nie s6 intensiefverreken nie. In die onderwys van Zimbabwe val die klem oorwegend op Afrikanisering en lewensvoorbereiding en daarna op die optimale hantering van kultuurdiversiteit. Onderwys in die Republiek van Suid-Afrika is steeds gesegregeer en hoofsaaklik monokultureel. Dit blyk uit die beleidsdokumente van onderwysbelanghebbendes dat 'n toekomstige onderwysbedeling dieselfde weg as die in Zimbabwe gaan volg. Die onderrig van samelewingsvaardighede word as prioriteit gestel. / Multicultural education is the consequence of universal trends towards democratisation. The United States of America, Zimbabwe and the Republic of South Africa were selected as exemplars to investigate the emergence of multicultural education. There are distinct similarities between this process and that of the development of segregated monocultural education systems. Opposition to the exclusive nature of monocultural education resulted in the establishment and implementation of multicultural education. In the United States of America multicultural education is enforced by legislation. Multicultural education in Zimbabwe is not applied as stringently. Zimbabwe's educational model emphasises Africanisation and the preparation for life, also proficiency in dealing with cultural diversity. Education in the Republic of South Africa remains segregated and predominately monocultural. From the policy documents of those parties interested in education it seems that any future educational dispensation will follow a course similar to that of Zimbabwe. The teaching of societal skills enjoys precedence. / Educational Studies / M. Ed. (Historical Education)
174

Técnicas de proteção e restauração em redes ópticas elásticas / Protection and restoration techniques in elastic optical networks

André Luiz Ferraz Lourenço 26 November 2015 (has links)
As redes ópticas estão passando por mudanças significativas, impulsionadas pelo crescimento exponencial do tráfego, principalmente advindo de serviços multimídia e armazenamento em nuvem. Esta demanda exigirá aumento da capacidade da taxa de transmissão para padrões como 400 Gb/s e 1 Tb/s. Nesse contexto, foi proposta uma arquitetura de rede com grade de frequências granular flexível chamada elastic optical network (EON). A EON divide o espectro de frequências em fatias (slots) de tamanho fixo e aloca grupos de slots contíguos estritamente de acordo com os requisitos de banda das demandas de conexão, implicando eficiência de uso do espectro. Com o aumento significativo da taxa de transmissão, acentuou-se a preocupação em manter a sobrevivência da rede, já que pouco tempo de queda no serviço pode acarretar uma imensa perda de dados. Neste trabalho, investigamos esquemas de proteção baseados em caminhos compartilhados (shared-path protection, SPP) e esquemas de restauração de tráfego. Avaliamos esquemas divulgados na literatura como o dynamic load balancing shared-path protection (DLBSPP) e esquemas de restauração como o traffic aware restoration (TAR) e bandwidth squeezed restoration (BSR). Avaliamos também uma heurística de alocação de slots chamada inverted dual stack (IDS). O DLBSPP utiliza balanceamento dinâmico de carga para computar os caminhos primários e de proteção compartilhados. O TAR executa a restauração dinâmica ordenando as conexões por granularidade de banda. O BSR utiliza a capacidade de contração de banda do EON para restaurar conexões por meio da política de melhor esforço ou de banda garantida, dependendo do acordo de níveis de serviço do cliente. O esquema IDS concentra o maior número possível de slots compartilhados em uma região do espectro. As medidas de desempenho dos algoritmos são avaliadas segundo as métricas: probabilidade de bloqueio, taxa de utilização do espectro, número médio de hops e taxa de restauração falha. As simulações computacionais mostram o bom desempenho da utilização do esquema IDS com DLBSPP. / Optical networks are undergoing significant changes driven by the exponentially growing traffic, especially coming from multimedia and cloud storage services. This demand will require increasing of the transmission rate capacity as high as 400 Gb/s and 1 Tb/s. Within this context, it was proposed the elastic optical network (EON), which is a network architecture with flexible granular frequency grid. EON divides the frequency spectrum into slices (slots) of fixed size and allocates groups of contiguous slots strictly according to the bandwidth requirement of the connection demands, providing high spectrum use efficiency. The significant increase in transmission rate put emphasis on the need to maintain the survival of the network, since the occurrence of faults in the network nodes or links can cause huge loss of data. In this work, we investigate protection schemes based on shared-path protection (SPP) and traffic restoration schemes. We evaluate schemes related in the literature, such as the dynamic load balancing shared-path protection (DLBSPP), and restoration schemes such as the traffic aware restoration (TAR) and the bandwidth squeezed restoration (BSR). The DLBP scheme uses dynamic load balancing to compute primary and shared protection paths. The TAR performs dynamic restoration ordering the connections based on band granularity. The BSR uses EON\'s band squeezing feature to restore connections by means of the best effort or guaranteed bandwidth strategy, depending on the customer\'s service level agreement. IDS scheme concentrates the maximum possible number of shared slots in a given region of the spectrum. Performance of the algorithms are evaluated according to metrics: blocking probability, spectrum utilization rate, average number of hops and failure restoration rate. Computer simulations show that the use of the IDS scheme improves the performance of the investigated algorithms.
175

Data Encryption on a Network

Luque González, Jorge, Arenchaga Fernandez, Ignacio January 2010 (has links)
In this project you can find a study about different encryption algorithms, which are use to safeguard the information on messages over the network. We have developed a client-server application which will send information through the network which has to be secured. There are two kinds of encryption algorithms, the symmetric and the asymmetric key algorithms. Both were used to establish the communication, the asymmetric algorithm (RSA) is used to set up a symmetric key and then, all the communication process is done only with the symmetric algorithm (Blowfish). / En este proyecto encontraras un estudio sobre diferentes algoritmos de encriptación, que son usados para salvaguardar la información en mensajes por la red. Además hemos desarrollado una aplicación cliente-servidor que enviara información a través de la red de forma segura. Hay dos tipos de algoritmos de encriptación, los simétricos y los asimétricos. Ambos tipos de algoritmos son utilizados para establecer la comunicación, el asimétrico (RSA) es utilizado para establecer la clave del simétrico y a partir de entonces se utilizara exclusivamente el algoritmo simétrico (Blowfish).
176

Aritmética modular, códigos elementares e criptografia

Barreto, Regene Chaves Pimentel Pereira 29 August 2014 (has links)
The main objective of this work is to treat the modular arithmetic of whole numbers, and show evidence of some types of elementary code such as Cesar's, A m, of Vigenere's, Hill's, RSA, Rabin's, MH and ElGamal, those found in cryptography, highlighting the mathematics which exists behind the function of each of them. We have studied the concepts of modular arithmetic and applied them to the study of matrices and determinants that are necessary for the function of these codes and for the evolution of cryptography. We also present some codes found in our day-to-day life, aiming to stimulate the curiosity of the reader into discovering these codes. Finally, for complementary information purposes, we reveal a brief collected history of cryptography. / O presente trabalho tem como principal objetivo tratar de aritmética modular dos inteiros e evidenciar alguns tipos de códigos elementares, a exemplo dos Códigos de César, Afim, de Vigenère, de Hill, RSA, de Rabin, MH e ElGamal, existentes na criptografia, ressaltando a matemática que existe por trás do funcionamento de cada um deles. Estudamos conceitos de aritmética modular e os aplicamos ao estudo de matrizes e determinantes que se fazem necessários para o funcionamento desses códigos e para a evolução da criptografia. Apresentamos ainda alguns códigos encontrados no nosso dia a dia, buscando estimular a curiosidade do leitor pelo conhecimento dos códigos. Por fim, a título de informação complementar, expomos um breve apanhado histórico da criptografia.
177

Elektronické zabezpečení zdravotnické dokumentace v prostředí zdravotnického IS / Security of Electronic Documentation in Medical Environment

Hauserová, Markéta January 2012 (has links)
Thesis is analyzing czech laws which are related to medical documentation. Describes the points  which are mandatory for information system, so the medical documentation can be stored electronically. Includes various algorithms for implementation of certain electronic signature and for  identification of person. This thesis deals with asymmetric cryptography, specifically RSA, DSA, and ECDSA. Describes the hash functions and their functions and their characteristics. Describes the principle of the certificate, ways of its obtaining, invalidation and their formats. Analyzes medical information system and suggests ways to create a program for signing medical records. Then based on that analysis, the program is implemented. At the conclusion of the work is discussed, if created program meets the criteria.
178

Design, synthesis and biological evaluation of TG2 transglutaminase inhibitors / Conception, synthèse et évaluation biologique des inhibiteurs de la transglutaminase TG2

Fidalgo Lopez, Javier 23 November 2016 (has links)
La transglutaminase tissulaire (TG2) est une enzyme de la famille des transglutaminases (EC 2.3.2.13) qui est exprimée de manière ubiquitaire chez les mammifères. Cette enzyme catalyse la formation d'une liaison amide intra- ou intermoléculaire entre un résidu glutamine et un résidu lysine. Ce processus biologique conduit à la modification post-traductionnelle des protéines. Un nombre croissant de publications associe la surexpression de cette enzyme et la déréglementation de son activité, avec un certain nombre de pathologiques humaines telles que les maladies neurodégénératives (maladie d’Alzheimer, maladie de Huntington, maladie de Parkinson), la fibrose tissulaire, certains cancers et la maladie cœliaque. Le développement d'inhibiteurs puissants et sélectifs de la TG2 est primordial pour identifier soit des outils pharmacologiques pour comprendre les processus biologiques dépendant de cette enzyme ou soit des candidats médicaments pour traiter les pathologies liées à la surexpression de la TG2. La majorité des composés inhibiteurs synthétisés jusqu'à présent agissent en bloquant de manière irréversible la réaction de transamidification de la TG2 en ciblant spécifiquement la cystéine 277 présente dans le site actif de la TG2.L’objectif de ce travail a été d’identifier et de sélectionner des molécules de faible poids moléculaire inhibant de façon sélective et puissante l’activité de transamidification de la TG2. Nous présenterons l’optimisation de deux séries originales de composés (synthèse, études de relation de structure-activité) comportant un noyau aromatique central de type naphtalénique ou indolique et une fonction acrylamide comme accepteur de Michael pour piéger la fonction thiol de la cystéine 277. Un certain nombre de composés synthétisés montre une inhibition nanomolaire de la TG2 (IC50 = 1.7-6 nM) avec un excellent profil de sélectivité vis-à-vis de TG1, TG6 et FXIIIa (IC50 > 10 µM). Ces inhibiteurs inhibent efficacement la TG2 dans des extraits de tissus et de cellules. Aucune toxicité apparente n’a été observée pour des concentrations inférieures à 10 µM d’inhibiteur sur les lignées vSMCs et SH-SY5Y. Les valeurs de KI, kinact et kinact/KI ont été également déterminés sur deux inhibiteurs sélectionnés (23b et 78f) pour leurs activités biologiques. La formation d’une liaison covalente entre la cystéine 277 de la TG2 et ces deux inhibiteurs a été prouvée par digestion trypsique suivie d’une analyse LC-MS/MS / Tissue transglutaminase (TG2) is a ubiquitously expressed enzyme of the mammalian transglutaminase (TG) family which catalyzes the formation of an intra- or inter-molecular isopeptide bond between a glutamine and a lysine, leading to the post-translational modification of proteins. An increasing number of literature has associated the over-expression of this enzyme, and the deregulation of its activity, with a number of human physio-pathological states like neurodegenerative disorders (Alzheimer’s disease, Huntington’s disease, Parkinson’s disease), tissue fibrosis, certain cancers, and celiac disease. The development of potent and selective TG2 inhibitors has become primordial to reach either a pharmacological probe, to understand the biological processes that depend on this enzyme, or a drug candidate, to treat the pathologies related with its overexpression. The majority of the inhibitory compounds synthesized so far act by irreversibly blocking the transamidation reaction of TG2. These TG2 inhibitors specifically target the cysteine 277 present in the TG2 active site. The aim of this work was the identification and selection of new potent and selective small molecules to inhibit the TG2 transamidation activity. We present the optimization of two new series of compounds (synthesis, structure-activity relationship studies) bearing naphthalene or indole aromatic rings as the central backbone structure. Both series present an acrylamide group as the Michael acceptor in order to react with the thiol group of cysteine 277. Several of the synthesized compounds showed a nanomolar inhibition over TG2 (1.7-6 nM) with an excellent selectivity profile over TG1, TG6 and FXIIIa (IC50 > 10 µM). These inhibitors showed high specificity on inhibiting TG2 in tissue and cell extracts. No apparent toxicity up to 10 µM was observed in vSMCs and SH-SY5Y cell lines. Their KI, kinact et kinact/KI were also determined on two selected inhibitors (23b and 78f) for their biological activities. The formation of a covalent bond between the cysteine 277 of TG2 and these two inhibitors was proven by tryptic digestion followed by LC-MS/MS analysis
179

License Management for EBITool

Krznaric, Anton January 2013 (has links)
This degree project deals with license management for EBITool. It´s about providing protection and monitoring for a Java Application via a license server, and the construction of it. An analysis that discusses the approach and other possible courses of action is also included. Additionally, it covers a discussion of a prototype implementation of the model solution from the analysis. The prototype is a Java EE application that deploys to JBoss AS7. It´s developed using the JBoss Developer Studio 5.0.0, an Eclipse IDE with JBoss Tools preinstalled. It exposes web services to Java Applications through SOAP via JAX-WS. Using Hibernate, the web service Enterprise Java Beans get access to a PostgreSQL 9.1 database via entity classes mapped to the database through the Java Persistence API.
180

Conception et sécurisation d'unités arithmétiques hautes performances pour courbes elliptiques

Francq, Julien 16 December 2009 (has links) (PDF)
La cryptographie basée sur les courbes elliptiques (ECC) est de plus en plus utilisée dans les cryptosystèmes à clé publique, notamment parce qu'à niveau de sécurité équivalent, la taille nécessaire des clés ECC est nettement inférieure à ce que son prédécesseur, le RSA, requiert. L'ECC conduit donc à implanter des circuits plus compacts que pour le RSA, ce qui indique qu'elle est plus adaptée aux circuits fortement contraints (cartes à puce, etc.). L'ECC a d'ailleurs bénéficié de l'amélioration continue de l'arithmétique (des ordinateurs et des courbes) ces dernières années, ce qui lui permet de se positionner comme un remplaçant crédible au RSA dans le monde industriel. Il est vrai qu'un concepteur de circuits cryptographiques doit chercher à améliorer les performances de son cryptosystème, mais il doit également protéger ce dernier contre des attaques physiques pouvant compromettre sa sécurité. En effet, des attaques efficaces dites "par observation" et "par perturbation" ont été mises en évidence. Le concepteur de circuits cryptographiques doit donc implanter des parades à ces attaques, également appelées contre-mesures. Cependant, l'ajout de ces contre-mesures ne doit pas d'une part ajouter de nouvelles vulnérabilités au cryptosystème, et d'autre part diminuer drastiquement ses performances. Ces travaux de thése proposent une nouvelle architecture d'unité arithmétique pour l'ECC. Il se trouve que les performances de cette derniére sont meilleures que la plupart de celles présentes dans la littérature. Ceci est essentiellement dû à l'utilisation d'une représentation redondante des nombres, appelée repréesentation à retenues signées. Le second r'ésultat principal de ces travaux provient de la protection de cette unité contre les attaques par observation à l'aide de l'état de l'art : ce faisant, nous proposons là encore la solution la plus performante de la littérature. Enfin, nous avons exploré la possibilié de protéger notre circuit contre les attaques par perturbation à l'aide du principe de la préservation de la parité. Cette dernière contribution amène des réesultats encourageants

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